According to this article, Hussein isn't there yet.
https://www.tuko.co.ke/277884-raila-meets-nyanza-leaders-lay-ground-obamas-anticipated-visit-region.html#277884
According to this article Mama Sarah has not been told by Obama he's coming. "But Mama Sarah said the former President had not told her to expect him yet they communicate frequently." https://www.the-star.co.ke/news/2018/06/10/obama-a-state-visitor-might-not-go-to-kogelo-says-mama-sarah_c1770665